Photoelectron Spectroscopy (XPS) is a surface-sensitive technique that provides information about the elemental composition and chemical states of the top few nanometers of a material.

What is Photoelectron Spectroscopy (XPS)?

XPS is based on the photoelectric effect, in which electrons are emitted from a material when it is irradiated with X-rays or ultraviolet (UV) light. The energy of the emitted electrons is characteristic of the element from which they originate and the chemical environment in which they are located.

How is XPS Performed?

• A sample is placed in an ultra-high vacuum (UHV) chamber.
• The sample is irradiated with X-rays or UV light, causing electrons to be emitted from the surface.
• The kinetic energy of the emitted electrons is measured using an electron energy analyzer.

What Information Can XPS Provide?

• Elemental composition of the surface
• Chemical states of the elements
• Presence of impurities or contaminants
• Thickness and composition of thin films
• Electronic structure of materials

Applications of XPS

• Surface characterization
• Failure analysis
• Corrosion studies
• Catalysis research
• Semiconductor device development

Advantages of XPS

• Surface-sensitive
• Provides information about both elemental composition and chemical states
• Non-destructive
• Can be used to analyze a wide variety of materials

Limitations of XPS

• Limited depth of analysis (typically only the top few nanometers)
• Can be affected by surface contamination
• Can be expensive and time-consuming